FILE - This undated file photo released by the Oakland County Sheriff's Department shows Jeffrey Maurer. The 54-year-old suburban Detroit man has been sentenced to life in prison for beating his 87-year-old father and 85-year-old mother to death with hammers. Oakland County Circuit Judge Colleen O'Brien told Maurer on Tuesday, Sept. 1, 2015, that his actions were "reprehensible and a shock to the community." (Oakland County Sheriffs Department via AP, File)
(The Associated Press)

PONTIAC, Mich. – A 54-year-old suburban Detroit man with a history of mental illness and substance abuse will spend the rest of his life in prison for beating his 87-year-old father and 85-year-old mother to death with hammers.

An Oakland County jury found Jeffrey Maurer guilty Friday of first-degree premeditated murder. He will be sentenced Tuesday.

Sheriff's deputies found the bodies of William and Gayle Maurer Jan. 19 in a vehicle inside the garage of their Rochester Hills home. They were bludgeoned two days earlier with two hammers and a heavy tea kettle.

Jeffrey Maurer lived with his parents. Prosecutors have said he wanted their money.

Defense attorney Michael McCarthy has said the slayings were "spur of the moment" and not planned.